In a glass-plate working apparatus of this type, a working head provided with a tool such as a cutter wheel for effecting desired working on a glass plate is mounted on, for example, an X-direction movable base which is movable in an X-direction, this X-direction movable base is mounted on a frame which is movable in a Y-direction perpendicular to the X-direction, and the X-direction movable base and the frame are moved in the X-direction and the Y-direction, respectively, whereby the working head is moved with respect to the glass plate, thereby to effect working at a desired position on the glass plate by means of the working head.
In the apparatus of the above-described example, the frame on which the X-direction movable base is mounted is supported at its opposite ends by a base or the like movably in the Y-direction, and is moved by moving devices at the opposite ends, respectively. The moving devices for moving the opposite ends of the frame are required to move the opposite ends of the frame accurately in synchronism, and if this requirement is not met, a difference in the amount of movement occurs between one end side and the other end side of the frame.
Generally, since the frame is disposed in such a manner as to be slidably fitted to guide rails provided on the base, and is moved in the Y-direction while being guided by the guide rails, if a difference in the amount of movement occurs as described above, the frame scuffs against or seizes or locks on the guide rails, which makes it impossible to effect smooth movement of the frame. Since the frame and the guide rails are fitted to each other with almost no clearance so as to attain accurate movement in the Y-direction, even if a very small difference occurs in the amount of movement at the opposite ends of the frame, there is a possibility of the occurrence of the above-described drawback.
The present invention has been devised in view of the above-described aspects, and its object is to provide a lass-plate working apparatus which is capable of effecting smooth movement of the frame even if a very small difference occurs in the amount of movement at the opposite ends of the frame.